A silicon dioxide–copper (SiO2-Cu) epoxy resin composite material for chip packaging was made by a mechanical mixing method with epoxy resin as the base glue and SiO2 coated with nano-Cu (SiO2-Cu) particles as the filler. The dispersion of SiO2-Cu nanoparticles in epoxy resin was studied using scanning electron microscopy and transmission electron microscopy. Meanwhile, the effects of the filler on the coefficient of thermal conductivity, the coefficient of thermal expansion (CTE), and the mechanical properties of the composite material were also studied. The results show that SiO2-Cu nanoparticles disperse well in the epoxy resin, the coefficient of thermal conductivity of SiO2-Cu epoxy resin composites increases with an increase in the SiO2-Cu filler amount, the coefficient of thermal conductivity begins to decline when the filling volume is over 25%, and the suitable amount of SiO2-Cu is 25% of the total volume. With the increase in the filler, the CTE of the composite decreases; when the SiO2-Cu filling amount is 25%, the material has good impact resistance and a long electromigration failure time for chip packaging materials.
